Fastest 8086 PC ever: NEC PC-98DO+ (not an AT nor 386, but with 16MHz)03/10/19
Not well known in Europe, but in Japan: The fastest 8086 PC ever is a NEC PC-98DO+ (one of the later models of the PC-9801 series), build around 1990.The PC has a NEC V33A CPU running at 16 MHz, which is something between a 8086 and a 80186, but not an AT compatible (or higher). It has an EGA